An unusual ship called Dorado Discovery has dropped anchor in the north channel of San Diego Bay, prompting inquiries from curious sightseers.

Seems the Edinburgh-based research vessel is on a layover between working charters, port district sources say. It’s equipped with scientific labs, ocean floor boring equipment and other gear for mineral deposit detection and water chemical analysis. It recently was leased by Odyssey Marine Exploration, which has conducted high-profile treasure hunting expeditions.

While no stranger here, in past visits the 321-foot ship has been less visible, tying up at the Tenth Avenue Marine Terminal or National City Marine Terminal while changing crew and replenishing supplies. Rest assured, though, it’s not drilling in our harbor, port officials say.